Metamath Proof Explorer


Theorem pfxccatin12lem4

Description: Lemma 4 for pfxccatin12 . (Contributed by Alexander van der Vekens, 30-Mar-2018) (Revised by Alexander van der Vekens, 23-May-2018)

Ref Expression
Assertion pfxccatin12lem4 L 0 M 0 N K 0 ..^ N M ¬ K 0 ..^ L M K L M ..^ L M + N - L

Proof

Step Hyp Ref Expression
1 nn0z L 0 L
2 nn0z M 0 M
3 zsubcl L M L M
4 1 2 3 syl2an L 0 M 0 L M
5 4 3adant3 L 0 M 0 N L M
6 elfzonelfzo L M K 0 ..^ N M ¬ K 0 ..^ L M K L M ..^ N M
7 6 imp L M K 0 ..^ N M ¬ K 0 ..^ L M K L M ..^ N M
8 5 7 sylan L 0 M 0 N K 0 ..^ N M ¬ K 0 ..^ L M K L M ..^ N M
9 nn0cn L 0 L
10 nn0cn M 0 M
11 zcn N N
12 npncan3 L M N L M + N - L = N M
13 9 10 11 12 syl3an L 0 M 0 N L M + N - L = N M
14 13 oveq2d L 0 M 0 N L M ..^ L M + N - L = L M ..^ N M
15 14 eleq2d L 0 M 0 N K L M ..^ L M + N - L K L M ..^ N M
16 15 adantr L 0 M 0 N K 0 ..^ N M ¬ K 0 ..^ L M K L M ..^ L M + N - L K L M ..^ N M
17 8 16 mpbird L 0 M 0 N K 0 ..^ N M ¬ K 0 ..^ L M K L M ..^ L M + N - L
18 17 ex L 0 M 0 N K 0 ..^ N M ¬ K 0 ..^ L M K L M ..^ L M + N - L